Before rubbing the apples, they are baked to heat, to soften them to such an extent that they can be rubbed through sieves.
Apples soften when they are cooked, because under the influence of heat and the acid present in them, hydrolysis of protopectin, which is located in the cell walls and in the intercellular spaces, develops. Other cells of the fruit glued by protopectin are slightly separated, some of the cells are torn, the fruits soften without losing their shape. When the heat treatment is too weak, when the apples are not sufficiently heated over the entire layer, they are too hard, under-cooked, after shparki. With too much and prolonged exposure to heat in apples with a high acid content, there is a deep disintegration of pectic substances, which is manifested in the cooking of apples and can lead to more or less weakening of the gelatinous ability of mashed potatoes. The latter is obtained with too liquid consistency.
In the process of curing, sterilization of the apple mass is achieved. Apples carry on their surface microflora, consisting mainly of yeast fungi. The latter are the causative agents of apple spoilage. They destroy the valuable components of the apple necessary for production (sugar, pectin, acid). The same applies to a certain extent to molds and bacteria on the surface of the fruit. At a temperature of 100 °, yeasts and other microorganisms of an apple die, at a temperature of 115 — 120 ° and above and prolonged heating not only microorganisms die, but also their spores. The temperature and duration of the sparks are calculated in production in such a way that they provide complete practical sterilization of the apple mass. This significantly increases the resistance of applesauce in subsequent storage.
Among other biochemical changes under the influence of corks, it is necessary to note the destruction of the oxidase system of apples (commonly referred to as the Malase enzyme), on which the formation of dark-colored oxidation products of tannins in apples - phlobaphenes - depends. In a healthy apple, its tannins and oxidizing enzyme system are not in a state of contact, which is necessary for chemical interaction. When the tissue of the fetus is damaged, tannins come in contact with enzymes, oxidize, causing the tissue to darken. The existence of malazy in apples would create the danger of darkening, especially when rubbed, due to the resulting wide development of the surface of the apple pulp. The heat of the crimper paralyzes the action of malaze, as well as other enzymes contained in the apple. From the latter it is necessary to point out the pectolytic enzymes that break down pectic substances, as well as ascorbinase and invertase, which are destroyed by sharp.
Of the secondary phenomena with sharca, it should be noted that the air is removed from the tissue of the boiled apples, the destruction of some coloring matter contained in the apple. On the other hand, due to the partial caramelization of sugars (in particular, fructose) under the action of heat, the scalded apple mass takes on a yellowish color. This yellowing is stronger, the higher the temperature and pressure in the spar apparatus.
A scoop of apples is produced by steam or water. Predominantly use low-pressure steam (about 1 - 2 ati). The pressure inside the sparder must not exceed 0,1 — 0,2 ati. When working under higher pressure, deep splitting of pectin is possible, as well as some yellowing of mashed potatoes under the influence of sugar caramelization.
The duration of the cork is 10 — 20 min.
From the point of view of preserving vitamin C in apple puree, it is very important that the apple cork be held at the most moderate temperature possible. According to VKNII , an increase in temperature in the spiked space by 1 — 2 ° in excess of 100 ° leads to a sharp increase in the loss of vitamin C in apples. When sharpening apples, conditions must be created that ensure the apples are heated quickly so that the total duration of the process does not exceed 10 minutes. Thus, in order to get a more complete ™ puree, it is necessary to combine the rapid warming of apples with the curing mode, which excludes the effect of temperature on apples above 100 °.
The acceleration of large-fruited apples warm while scalding is achieved by carving an apple core along its longitudinal axis by means of a special machine.
In small enterprises, apple scrubbing is practiced in water in ordinary steam boilers. In this method of operation, the mash is significantly diluted and, in addition, the water going to the corks is extracted from. apple mass a significant amount of valuable extractives. Sponge water should be used to dissolve the preservative added to the mash, or to wipe the wiping with a secondary scar before wiping it; otherwise, significant losses of apple extractives are obtained. When water splash inevitably lost vitamin C, which is easily transferred from apples to water.
A well-known advantage of water curing is that it provides a more moderate hydrolysis of pectic substances than steam, as in the first case, the apple temperature does not rise above the boiling point of water.
Apples for continuous operation of various types are used for large enterprises apple steam machines: The main requirements for these machines are as follows: a) maximum ease of loading and unloading apples on the bacon; b) avoiding jamming and caking of apples inside the parmer during the mash , c) uniform scaling of all apples, d) minimal contact of apples with corrosive metals,
e) reduction of losses by correct removal of sparks water and condensate and their use, e) elimination of steam release from the evaporator to the production area.
Soviet engineers have developed a number of designs of continuously operating screw and mine type vaporizers.
At the station of preparation of fruit and berry puree of the Zhytomyr confectionery factory there are two screw-type evaporators.
The screw apparatus (fig. 4) consists of the 1 screw, enclosed in one or two located one above the other trough-shaped 2, 3 bodies. The latter are made of stainless steel (or wood) with a hermetically closed lid. The stainless steel auger has an 4 hollow shaft connected to the steam line. On the surface of the shaft are holes for the bubbling of steam. Loading apples into the auger is done through the 5 bunker.
In the process of curing, apples move with augers through the upper and then the lower body; Squandered apples are unloaded through the 6 hatch.
When sharpening sulfitated apples in this steamer, it is necessary to provide exhaust devices for the removal of sulfuric anhydride.
Shpariteli this type are characterized by their compactness and high performance to 12 tons of apples per shift.
Fig. 4. Screw shparitel.
More attention should be paid to mine-type vaporizers. In them, continuous corking is carried out by moving the apples (or other large fruits) due to the gravity of the pasted raw material and the static pressure of the overlying layers of apples on the underlying ones.
These vaporizers are distinguished by low cost (simple wooden construction) and the absence of moving working parts inside the apparatus. They are well justified in practice.
The Lysyansky steamer (fig. 5) consists of a vertical receiving box 2, which ends with an inclined box - 1 steamer. The angle of the bottom of the evaporator to the horizon 20 °. Steam bubblers are laid along the bottom of the vaporizer. The raw material is fed through the bucket elevator from above to the receiving part of the apparatus, from where it enters the evaporator. At the exit from the vaporizer, the 3 thrust valve accelerates, slows down or temporarily stops the output of skimmed raw materials. This was achieved by regulating the time and degree of the crimper. Drive valve ts Yun g from a gear with a handwheel. Upon exiting the steamer, the stewed apples are sent directly to the loading funnel of the wiping machine.
Fig. 5. Shparitel Lysyanskogo.
The Dmitriev scalder (Fig. 6) works on the same principle, but differs in some details of the device. It is a wooden vertical tube divided by a longitudinal partition into two shafts. Apples are continuously fed by the elevator to the upper opening of the apparatus, and the cooked apples continuously go out from the lower outlet.
In each compartment of the apparatus along its vertical axis there is a bubbler tube, which does not reach about 0,5 m to the upper edge of the apparatus. Steam in the bubbler is supplied from below. The narrow cross-section of the shaft (0,5 X 0,5 m) and central The (axial) location of the bubbler creates conditions for even scalding of apples. The holes in the bubbler tube are arranged in decreasing amounts in the bottom-up direction, which ensures the maximum steam supply at the bottom of the shaft and the minimum - at the top.
In order to avoid liquefying the puree with condensate and the juice produced at the bottom in the lower cone-shaped part of the apparatus, in its rear wall opposite the discharge opening, longitudinal slits are made about 10 mm wide through which the mixture of condensate and juice flows into the funnel and from there through the chute is collected by either in a different way.
To ensure even settling of apples over the cross section of the mine and for directing condensate mixture with grating for the swelling of their juice from the discharge outlet is arranged ledge.
The discharge opening is made in the form of a slightly protruding pipe, which is blocked by a metal valve connected through a comb and a gear with a steering wheel. The duration of the sharkey is controlled by this valve.
In the described apparatus, the fruit is performed by direct exposure to steam. This ensures better use of steam heat. However, upon condensation of steam in the mass, the latter liquefies accordingly. Therefore, in the Dmitriev et al. Steamers it is envisaged that the resulting liquid should be removed from the boiled apples in order to increase the dry matter content of the puree. A mixture of condensate and apple juice, which was drained from a steamer, is collected separately from mashed potatoes and used in various ways. For example, it is subjected to thickening and added to the puree. To reduce the amount of condensation produced, it is very useful to organize preheating of apples to 50 — 60 ° in front of the spar with deaf steam in special screw heaters or in hot water baths.
In small enterprises, for apple steam tubes, cupboard, drawer, closed, conventional, and Genet steamer types used for steaming potatoes in alcohol and starch production are used for steaming. These steamers differ from each other by the method of loading apples (direct loading, loading in sieves on trolleys), by the method of unloading of boiled apples, the method of steam heating (coils or bubblers), etc.
The mode of splicing apples in specific production conditions is established depending on the type of the used scraper, steam pressure, variety of apples, their size and degree of ripeness.
In practical work, the sharks should be guided by the following provisions: all apples should be as flat as possible and uniformly spiced, and after apples, the apples should go whole, as this prevents the loss of apple juice, especially when the steam cleaner is not in direct connection with the rubbing machine . When apples overheat, i.e. when they are perepparka, part of the apples boil down. If the apples are underpowered, then in the zone adjacent to the central part of the apple, there are areas that are not exposed to high temperatures and contain intact oxidases. As a consequence, it is possible darkening of the apple mass, usually starting from the core layer.
Wiping shparenyh apples
Steamed apples are sent for wiping, the main purpose of which is to separate the inedible part (stalks, seeds, seed box, etc.) from the pulp and chop the latter.
Apples rubbed on various designs machines. The most common type horizontal wiper (fig. 7).
Fig. 7. Diagram of the device of the cleaning machine for scooped apples.
Prepared with a knife apples (or other fruits) are fed through the loading (6 funnel into the cylindrical body of the machine, mounted on the 3 shaft and consisting of a double-sieve 1.
An auger is mounted on the shaft on the inlet side of the machine, pushing the post - drank apples to the crushing blade 4, from there the pre-shredded apples go through the 5 spreading grid into the working space of the machine, in which two or four bends are rotated, mounted with special holders on the same shaft. Attached rubber pads along the outer edge of the 2 beat. The protruding outer edges of the latter form a small gap with the inner surface of the sieve cylinder, the value of which can be adjusted within 2 — 5 mm by displacing the blow holders.
The number of revolutions 500, per minute.
Under the action of centrifugal force developed by the rotation of the blows, the split fruits are thrown to the periphery, pressed against the grid of the cylinder and the pulp of the fruit is forced out through the holes in the receiver of the machine.
The remaining parts of the apple inside the cylinder (i.e., “wiping out”), retained by the sieve, are removed from the machine through the hatch.
Litter advancement to (exit occurs due to the fact that the fruits entering the machine body receive, in addition to rotational, also translational motion in the direction from the hopper to the ejection hole of the wastewaters. This is achieved by mixing the blower towards the generator of the machine cylinder at an angle , t. n., the angle of shear or advance. With an increase in this angle, the translational speed of the fruit mass increases, thus reducing the output of the fruit pulp through the net by increasing the number of flushes. The amount of wiping is reduced by increasing the yield of fruit pulp.In practice, the angle is chosen depending on the type and variety of fruit in the range from 1,5 to 5 ° so that the attritions contain the minimum amount of fruit pulp.
The rate of advancement of the leach depends also on the size of the holes of the working sieve of the machine, which regulates the passage of the rubbed pulp and the degree of grinding of the latter.
Apply nets with a diameter of holes 1,5 — 2 mm for rubbing spiced apples. During the secondary rubbing of mashed potatoes immediately before using it in the production of jelly-pastilles, nets with smaller holes are used (from 0,5 to 3 mm).
Wiping machine manufactured in different sizes with a capacity of up to 1 10 t / hour (for apples).
All working parts in contact with mashed potatoes should be made of non-oxidizing metal. Often the copper grids used on the rubbing are a source of copper and fruit puree contamination. The use of parts made of copper or iron adversely affects the stability of vitamin C of the raw materials. The most suitable material for this purpose is stainless steel.
When working on wiping machines, it is necessary to pay attention to the even and, as far as possible, continuous supply of cooked apples, as otherwise the machine can be overloaded. Particular attention should be paid to the prevention of foreign objects from being rubbed due to the danger of spoiling the mash and breaking the mesh.
It is very important for the control of the release of mashed potatoes, which depends on the quality vyterok (vyterki should be possible to fully exempt from the pulp). Do not allow crushing of seeds, as this may lead to the transition from seed and amygdalin mashed appearance in the last paragraph of bitter taste.
Primary mounts contain about 24 — 32% solids, including 3 — 6% sugar, 1,0 — 1,5% pectin for calcium pectate, 10 — 12,5% crude fiber.
Rubbings are usually subjected to secondary rubbing to extract an additional amount of gelatinous mash from them. For this purpose, they should be collected immediately from under the cleaning machine in the collections, equipped with coils for heating. Rubs are poured over with two to three times the amount of water by wiping, and the whole mass is spun again for 30 minutes, then re-directed to the cleaning machine. The resulting puree is used for lower grades of marmalade, waste - secondary rubbing - for the production of pectin. If the content of pectin is too low or if it is impossible to process them locally for pectin, they are immediately utilized for feed.
For transportation of puree from rubbing to the next stages of production, pumps of mainly kolovratnogo type are used.
Sometimes it is beneficial (depending on the location of the equipment) use of screw devices to move the mashed potatoes. The augers can also be used to transport scaled apples for rubbing and rubbing from rubbing.
Apple puree, like other types of fruit and berry puree, is a substrate of a predominantly carbohydrate character, favorable for the development of yeast, molds and some acid-forming bacteria. Getting into a puree, yeast cause alcohol fermentation in it. Since the initial microflora of apples dies out in the process of crimping them, contamination of the mashed potatoes with these microorganisms is possible only as a result of the so-called “secondary” infection at further stages of production following the grease. The natural protective factors against microbiological spoilage of the puree are its acidity, a relatively high concentration of hydrogen ions (pH) and a thick, viscous consistency. The higher the acidity and viscosity of the puree, the better it resists the development of yeast in it. However, to protect against damage to the puree, intended for long-term storage, it becomes necessary to preserve it artificially, for which the following methods can be applied.
Sterilization of heat
Fruit puree is sterilized in cans (with a capacity of about 10 — 15 l) of white tin or glass, similar to other canned fruit and berries. With proper sterilization, complete depletion and the best preservation of applesauce are achieved. The disadvantages of this method of canning are its complexity and high cost, which make it unprofitable for bulk production.
Drying. Reducing the water content in the puree to 15 — 20% by drying also provides the necessary guarantee against damage to it during storage. (The method of drying mashed potatoes will be described separately).
P about d in and r to and with sugar. When boiling apple puree with sugar in a ratio that ensures the sugar concentration in the product is not lower than 60 — 65%, the development of microorganisms is strongly delayed. Harvesting apple puree, as well as other types of fruit and berry puree in the form of preparations, is widely practiced in the confectionery industry. However, with this method, the preforms are lost to some extent the aromatic and gelling properties of the mashed potatoes. Therefore, applesauce, harvested by boiling with sugar, is not very suitable for the production of jelly-pastilles, it is used in this form mainly for fillings.
Puree, subject to freezing, immediately after curing, mixed with sugar in an amount of about 25% by weight of the entire mixture. Poured into barrels (or into cans, as well as into cans of special compressed cardboard), mashed potatoes are subjected to rapid freezing in unclosed barrels in freezers with air circulation. After freezing the mashed potatoes or jars are clogged. In this case, the importance of the mash is freezing, which depends on the temperature, air movement, size and material of the container for mashed potatoes. Freezing the apple puree does not affect its jelly-forming and taste properties, provided that the puree is not subjected to prolonged warm storage after thawing.